Pump



Oct. 28, 1941. A, D FERGUSAQN Y 2,260,306

PUMP

Filed April 16, 1938 5 Sheets-Sheet l Oct. 2S, 1941. A, D FERGUSON.2,260,306

PUMP Filed April 1e, 1938 5 sheets-sheet 2 7 l y 30 30 18 f3 12 u,

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063 .Qn-J

Oct. 28, 1941.

A. D. FERGUSON 'PUMP Filed April 1e, 19:58 5 sheets-sheet 3 /7 15 18 ii--l/Z,

f5 M 39 a/ y/ "M 55 1/ 000,0 093 .63 0 W 71 y?. 7375 w, oo oo l? 774'yryz 31 w27 51 5P@ (9h95 ziunZ/or:l Q Zexa nderlZ/Tzyyd'wz ,CML 4':Awamoctu 28, 1941.

A. D. FERGUSON y PUMP Filed April 16, 1938 5 Sheets-Sheet 5 '4M/WM,

Patented Oct. 28, 1941 v.tzt-ogm;

Alexander D.

Ferguson, Michigan City, Ind., as-

signor to Sullivan Machinery Company, a cor- 10 Claims.

This invention relates to pumps, and more particularly to improvementschamber, diaphragm type which are especially useful in pumping liquids.

In oil well drilling, particularly where rotary drills, such as diamondcore drills, are employed, it is desirable' to use mud fluid as acirculating fluid, so that the fluid, asv the rod line rapidly rotates,is throwny by centrifugal action into the walls of the drill hole toplaster the sides thereof, thereby to reduce the possibility of caving.Mud fluid is usually pumped into the drill hole under pressure by aconventional liquid pump of the piston type. It is relatively thick andoften contains acid which exerts a corrosive action on the pump parts.Moreover, the conventional pumps are comparatively heavy, and it isdesirable to cut down rtoa minimum the weight of the apparatus, so thattransport thereof may be madeless difllcult. f

A primary object of provide a liquid pump, especially designed to beporation of Massachusetts Application April 16, 1938, Serial No. 202,374

in pumps of the multithe presentinvention 'is to used in pumping mudfluid in oil well drilling, inl

which the objectionable features of a conventional liquid pump are, to asubstantial extent, eliminated. Another object is to provide an improvedpump of the multi-chamber, diaphragm type having novel means foractuating the pump diaphragms, together with improved controlling valvemeans for regulating the pumping action. A further object is to providean improved mud fluid pump especially designed tovuse in oil welldrilling, for circulating the mud fluid in the drill hole. A stillfurther object is toprovide a pump of the above character which isrelatively simple and rugged in design and extremely compact and lightin weight, well adapted to meet the demands of service in oil -welldrilling work. Yet another object is to provide an improved pumpespecially designed to use generally in pumping liquids, and which isespecially applicable to the pumping 0f liquids such as acids, whichexert la corrosive action on metals. Still a further object is Ytoprovide an improved diaphragm-type, pressurefluid-operated pump havingimproved distribution means for vtheoperatlng fluid. Yet another objectis to provide an improved vacuumactu, ated valve mechanism. Stillanother-object to provide an improved trigger-type valve actu-r atingsystem. Other objects and advantages of the invention will, moreover,hereinafter more fully appear. i In the accom shown for purposes whichthe invention may ying drawings there are of illustration two formsassume in practice. y

In these drawings,-

Fig. 1 is a plan view of one ment of the invention. I

Fig. 2 is a side elevationalview of the pump vshown in Fig. 1. i

Fig. 3 is a horizontal sectional view ltaken substantially on line `3'3of Fig. 2, and-with its showing partially diagrammatic.

Fig. 4 is a fragmentary vertical sectional view taken substantially' online 4 4 of Fig. 3.

Fig. 5 is a view similar to Fig. 3, but with parts omitted and with anumber of the parts shown differently positioned.

illustrative embodi- Fig. 6 is a view' in longitudinal section talrensubstantially on line 6-6 of Fig. 1.

Fig. 7 is a vertical sectional view taken substantially on line 1-1 ofFigs. 2 and 6.

Fig. 8 is a detail sectional view, on a larger scale, showing a portionof the securing means for the pump diaphragm.

Fig. 9 is a detail view plate.

Fig. 10 Ill-III of Fig. 9. H

Fig. l1 is a horizontal sectional view somewhat similar to Fig. v3,showing anotherform of the invention.

Fig. 12 is a detail sectional view,

In the illustrative embodiment of the invention shownin Figs. 1 to` 10inclusive, the numeral I generally designates a pump ofthemulti-chamber, diaphragm type, genemlly comprising a base 2, apumpchamber casing `3, a motor driven pump I and a control valve mechanismgenerally designated 5. The pump chamber casing isherein shown ascomprising a pair of -opposite end plates Ii, 6 and a. central bodyportion 1. A pedestal 8, herein integral with the pump casing 3 on thebase, while a frame 9 supports the valve mechanism on the base. The pumpcasing body 1 and the heads 6,' 6 cooperate in providinglaterally-spaced, circul vertical coaxial diaphragm chambers II and i2,and the bodyV 1 providesa` I3, intermediate pump chambers Il' and I5 anda top discharge chamber I8. As shown in Fig. 3, the chambers Il and I6are divided by a diagonal vertical septum Il and communicate throughperforated, disc-like strainer plates I8, I8 (see also Figs. 9 and 10)with the diaphragm cham-'- bers II and I2; `and as shown in Fig. 6,thepump chambers Il fand I5 are spaced from the dis-` charge chamber I6by a generally horizontal wall showing a strainer screen wall 20. Inletvalves 2l,

is a detail sectional view taken on line the body 1, supports bottomliquid-'supply chamber` control the ow of liquidfrom the supply chamberI3 to the pump chambers |4 and I5, while 2,260,306 i 88 betweenthe.heads 84 and 85 and 89 between' discharge valves 22, 22, which may alsobe of any suitable type, control the discharge of liquid 'from the pumpchambers |4 and I5 to the discharge chamber I8. The supply chamber isprovided with a supply pipe 23, and the discharge chamber |8 is providedwith'a discharge pipe 2 4.

As illustrated, clamped betweenjouter annular surfaces'on' the pumpcasing body and the detachable head members 8, 8 are iiexible diaphragms28, 28, herein. preferably composed oIfav rubberized material, havingtheir sides exposed 1 to the liquid to be pumped impregnated orcoated'with a suitable acid-resistingsubstancel As phragm-clampingsurfaces on the pump casing body and heads, between which the diaphragmsare clamped, are serrated or roughened at 21, so

that'when the heads are clamped in position on the pump casing body, asby clamping bolts 28,

' shown most clearly-in Fig. 8,'thecoactinlg dia-I theheads 85 and 88.'Ihe width of the grooves is such that each groove is capable ofconnect-l ing an adjacent pair of the portlngs 41, 48, 49, 59 and 5|.Rods 1| and 12 are xedly mounted,

coaxially with the valve 82, in the latter, and f project from theopposite ends of the valve, being surrounded byannular spring-receivingreceses 13'and 14 openingthrough the yendsof the valve element.

in the bores 54 and 51. Connections 11 and 18 connect the motor spaceswithin the chambers II and I2, when the diaphragms 28 are in suchpoand51.

the annular portions of the diaphragms adjacent their outer peripheriesare securely held. It may be .noted that the remaining portions of thediaphragms 28 are movable withinv the diaphragm chambers-II and I2.andform movable ,l boundaries lfor the portions of- :such chambersv which-arein communication with the .pump chambers and I5 respectively, whilethe por,- tions oi' the diaphragm chambers whichlie to the `outsides ofthe diaphragms` respectively constitute motor spaces later to` bedescribed lin more detail. 'I'he particular portions ofthe "diaphragmchambers I I, I2 which operateas motorspaces, are connected throughsuitable gratings 30,'with passages 3| Vand'32 respectively, which eachconstitute alternatively working fluid supply and exhaustv passages, andlead to'and are controlled by the valve mechanism 5. f y Referringnow-in detailltofthev valve mecha*-` nismya d more particularlytoFigs.'3',`4 and V5, it win i `cludes a tr ated withy the chambers""||*and I2.'A 'The valve 4|, 42 and 43. 'I'he chambers 40 and 42 'respec-L'ansversely extending valve cliestmex-y ber y35, herein connectedthroughcouplings 38 and 81 with the heads 8, 8 respectively associ` ltivelyrcommunicate'with the passages and 32. The 'central annularchamber 14| yis a supply chamber, and the chambers 39 and 43, which'are`the outside, i. e. relatively most remote, cham- 3 bers, constituteexhaust chambers. -'I'he bore'38 "y y is provided withy av liner 145suitably ported to] provide communicationhbetween itsinterior and theseveral annular chambers y39 to. 43 .through'f annular portingsyrespectively designated 41, 48,

The ends of the valve chestmember 35 are pro;v l

videdv with closure members l52, 52. *Each of these is'provided ywithafprojecting'portion' of reduced size, ther left-hand head `in` Fig.'`Il having 1 its projecting portion v 53 vprovidedv withcoaxial bores 54'and 55,'and the right-hand head mem# ber`52invFig. 3 havingitsreduced-portion 58 i l provided with a bore 51 corresponding "tovthe* .bore 54 and having a bushing'-` 5 8 bored at 59 to Suitablesprings-19, having sulilcient strength trolof a valve 82, and'dischargesthrough a line 83 tothe annular space ,4| in the valve chest memberv35.The annular exhaust spaces 39 and 43 are connected by lines 84 and 85respectively with a return line 88, which maybe connected through aby-pass 81 withthe pumpintakezor v through a valve-controlled connection88 Awith fr the liquid tank 8|. The rod 12, which isreciprocable, asabovexexplainedfwith the piston, valve 82, projects through the outerend of thebushing. 58, and is provided with a pair -of annular Withthese grooves, rollers grooves 9| and 92. 93 .carried by' pivoted arms94 mounted for swinging movement by pivot --pins 95 .upon the` I head52, are adaptedtofcoact. Springs 98 con-v '.nectadjustably locatablepins 91 carried in thearms 94 and cause 1 rollers- 93 to exertadditionalholding force upon the. rod-,12, depending upon the location of thepins91. r Y z It should be understood vthat the pump 4 is of Vsuch acharacter "that it isr capable of vcontinued operation against veryvhigh pressures. Astaged centrifugal pump .would be one type which couldbe used. i The liquid system, includingthe motor spacesin the diaphragmchambers, the connections" 3| `and 32, the connections 11 and 18thedistributingfvalve and vvalve chest spaces, :the n piping 83, 84,85, 88and 81 andthe pump 4, -will be'provided with a quantity oiA liquid suchthat 'at the instant whenthedistributing valve is about tu be `thrownall thespaces to which it is conv nected to deliver iluid will be-illedwith liquid, and there will be sufficient fiuidin the spacesconnected to the intake of the pump'4 so that, while a suction. sumcientto eiectmain pump' intake will be provided, vthe. pump 4 will stillfhaveliquid at its intake. 1- v With the further understanding that thepressure necessary to move'the valve 82, when .the

latter is held stationary bythe rod 12 and trigger mechanism, exceeds`that'which is exerted'fby the plungers 15`or 18 and springs19 exceptwhen' the diaphragins have v completed their normal pumping movements,the operation of the-mecha-` nism will be readily understood. 'I'he mudil'uidr or other liquid to be pumped'is taken-into the intake chamberAI3, through the -pipe 23,'v and is adapted to be discharged from thedischarge chamber through the discharge .line 24. With the'position oi'the -parts shown in Flg. 3, the por- L tion o! the-chamber I2 to theleft of the-dia- Annular pistons 15 and 18 ksurround Y* the rods 1| and12 respectively, and lit and slide lsp'ac'e 38, thel discharge' line land 181s also'oi such phragni" 28 'and the v'pump' chamber'- 'I5 arefilled 'W'ithf liquid "to be displaced, The ch'ambe l'l hasthefspacet'its `Ieftfsitie filled 'withmtive liquid; butris connectedwithv the intake-"side *of the hydraulic' "umpv-4.- yThe'chamber |4lsiilled withfmud' iiuid 'awaiting' entrance toV the portion of thechamber |I which will beto'the rightjbf the 'diaphragm 26 as thatdiaphragm `movesl to Now, the voperation of the arranged asin'lFig.3--will force liquid'under 'con-f `sideable pressure'thrcugh the li e88, the an'- vnular chamber! 4 I and' the 'porting `4'48,`V the" valvegroove88,"the porting 50,"the annular chamber and conduit'32, andtheholesv in the grating, tov act upon the right-hand side of the diaphragm26 arranged vin chamber I2; causing -thediaphragm to displace fromchamber"v IZtheYinud fluid thereinand thereby effect a 'discharge'v 4oi?mud fluid fromA the' pumpfchaniber/ 5 through 'the ydischarge valve'rn'ec'liianismly -22 thev discharge chamber I6, 'and t Aencethroufg'h'fthe'discharge line 24'. Siniulta'neously,` the 'motiveliquidwithin the chamberl I Ito the leftfof the left hand'di- 'aphragm 26Awillbe withdrawn throughgthe foon;-

4nection' 8 I', the annular groove 40, the porting 48,

thegroove 81l in* the valvefthe yporting 4l, 'the y 84 and'r the" returnline 86; arid the left hand diaphragm'f 'will' be caused to movetoe'irectl-tne'entryvof aoiaphragm chamber Aiull ofliquid from the"int'alt'e Achamber I4 tothe chamber II. *When the'diaphr'a'gm'26associated Vwithffchar'nber' I2 li`asf i)eenvv moved to theposition'shownin Fig; fco'ntinued operation of the pump willincrease'thel pump discharge pressure "within the 'chamber y I2, vandsince, with the"'diaphrf'gm` member offchar'nber I2,v moved pump vtiwitrrther parte vom from theV positionshownv in 'Fig.`^3,'- thepressure y acting upon its right When` this pressureA has increasedsufliciently -to compressthe spring'within the spring chamber i 51, aswill occur when the piston'l' moves tothe leftin Fig; 3,-to a positioncorresponding to` that o irfthe piston 15'; apresvsure sumcient-to 'movethe r'o'd" "I2l longitudinally despite' vthe action or fthe rollers `93,`will be developed; and thevalve:` 82

groove '82 and hold the valve 'inthe position of Fig. 5 until conditions'for a 'reverse iiow are brought about byv thedevelopment `oi "a highpressure to act upon the outer end oi the piston 15.-

It will be observed that the springs actingto move the piston valve 82in'opposite directions are of such lengtluandthat the travel o i thepistons length, `that even attire completion of valvej'throwing there isa'prepon derance oipressure'in the throwing direction until after thepiston 15 or 18 which has effected the throwing starts to lmove'outwardly in'` itsrespective cylinder, It should ber noted with'respectto Fig'. 3 that this is kan instantaneous position, so to speak, andthatkthe piston 18 -is shown in the position it 'occupied' to effect thethrowing of thedistributing valve A82, instead ,of in the position inthe'left-handy Aend oi' theI cylinder 54 which it will yoccupy almstimmediately' alter the position of'the distributing valve shown` in Fig.3 isestablishec'l. It will be ynotedV that the points of4 communicationof thepassages l171 and 18 .will be so related' relative tothediaphragmv clmbers that any small rises in pressure-during n sideisenabledfthrough the connectionfI8',"toact upon thelpiston' '18','Kthatipiston will b'e subjected'to the increased pressure.

Qin

' grooved to enable `portings for connecting chamber l 4I', dischargecha l `mediate' the central chamber*4|"'1andf each 4of lthe "chambers lspacejthsef numbered respectivelyz40' `andra-42' material as Alnico.

.the 'chamber in which the lvalve `:hand endl oi 'the starting ofdiaphragm' movement 7 will: .not s be transmitted the facesv of theplates.L or. heads. 8',Y 8 coulda-.be l action,I onv a larger diaphragmarea-*of 'the pumping i fliquid, immediatelyffs;r upon sunplvt'thereof,if 'desired'. l 1'- 1 AThelfv'alv'e mechanism described,l is:positiveein action; A does not lhave any tendency'ito `stop inanintermdiate position; and lisziirmly heldin itsy differentworking=positions\fwhile inl them. -By appropriate/selection i of materials,:the .pump chamber' ,'gratings, 1T the valve mechanisms. and the'diaphragme' can be' made to berv very durable and'largelyimmune toinjury by the mud-fluid o'raci'd;y "A light" and` powerful i pumpinga-u'nit isi provided' by they structure described.l -l ri.

lligy.i-11=shows a different embodiment Yoffthe invention; v:The details'ofi the fpu'riip `casing ibody, the pumpcasing .heads .arid most' ofthe'structure 'of 'the distributing 'valve'fchamber' arezthel same as the astructure disclosedin-vliigs; 1 .tol 10..'in-

clusivebut' instead" o! 'fedectingf high@ pressure the holding-of thevalvein its opposite :positions is effected by' magnetic, vratherthanftrigge'rtype; detent mechanism.

'Bearing 'in mind thatcorrespondingun- `changedfparts ywill be lnumberedthe same 'asin I ber4 observed that lthe jvalve Fgsl Y1 to 10,'it maymechanism 51 of Fig; 11 'comprises a Lvalver chest member '-35' havingsi 'liner "45t pbvidedV with its interior'y at its longitudinalfc'e'nter `with Yan "annularffluid` supply andl its fends'l "withannular nuid mbers 38 'and43';` ndflinterand connectedthrough conduits3|' and13lr 'with thechar'nbers II'and I2.'` The valve 182i' isfherei'ndesirablyf'made of f light `material; as, lior example; of aluminum','and-` is provided at its'A opposite ends withI platesof'ironfor othersuitable n material which may A"co'act with vstationary 'per- |00flxe'dly arrangedlfin the `heads^|01 and'Y |08' oi'- thevalve'fchestf-body 38'; The headsy |01 and |08 are preferably madeof-nonmagnetic material'and'the magnets |85 and |08 may advantageouslybemade 1 of such Each of :Lthe heads |01 and |08 isprovided withvachamber I|0` containing alspring-pressed 'checkv valve f| I having vastem II2` projecting into'the boreo'rthe liner vsuihciently far so thatwhen'the valve'il'is in either of its extremeopposite positi'onspits endshall strike the lstemfof 'one Vof the'valves `I I2 and open the latter.The-left-handfendof |52" is` `reciprocable, is connected ing a checkvalve the passage 3|', with that passage andthe rightconnected* lthrough"a passage I I5* and'. a check valve `I I8 opening" towardstheipassage', with the latter;

` 83;'connected` with th kchamber 4I. Lines-84 and 85 connectthe spacesl38' fand 43-withva returnv line 86 which'connects-throu'gh *a Ioy-passWith the intake Side `ofthe pump "Aliquid reservoir-is providedat tothepistons andtlrr Obviously through' a` passage I3,1hav I |I4` thereinopening Atowards distributing vvalve 'chamber `Ais` Theforce pump 4 hasitsrdischarge' 8 I, 'and its 'fcomznunicacompletes this rright-'handside tions with the return-line '86 and with theA suction'V side ofrthepump` 4 arerespeetively con- 4 trolled by valves and 82, all as in F'lg.3.I -Ob- Y .v1ous1y," by suitablecontrol of the valves AUZ- and 'y 88therequisitef quantity of motive liquid'may be insured in the hydraulicsystem. Desirably,-the

' linerlifl'andpossibly'also the entire valve chest member f35.".may.be-lmade Vof non-magnetic f material, vSeniat `the accionarthe'distributmg Letters Patent is: f

at atmosphericpressure into' the right-hand end ofthe valve vchest,thusrelievingthe vacuum.

The magnet-i |705; nowy holds thevalve 6 2 in the right-hand position..-The-pump'yknow pumps liquid'4 throughr the passage V32- to act uponthe of f thenright-hand diaphragm 26;V andtheliquidtothe. left ofitheflefthand diaphragm 26- is pumped-out. yAssoon asthe' diaphragm-Ninthe chamber Il reaches its left- 'hand' extreme; position, a substantialvacuum willy be-produced'in thep'as'sage 3|' and this-.will

result f inria reduction in .l pressure, .Within the Yspace to the leftof the Ivalve A62v in the chamber in which the `-f1 atter moves, sogreat vthat the -diilerential in pressure-on the opposite ends of thevalve will overcome the holdingforce of the magnet |05, .and lvalve 62will be .snapped-.over Zito its 4'left-handiposition. It will therelopen f valve l l lin .the head 108, Vbreaking the. vacuum;yand'jbepheldinfitsnew position bythe magnet klliil. vIt willbe.v notedthat thev pumping .fluid cannot r-be .discharged from either the.Ipassage 3|! or the passage 32' into either offthe opposite ends-ofI thelchamber in which the valve. 21 moves... The'quantity ofliquid in thepump operating system will bechosenso that itwill be less :thanvsufcierit completelyfto ll the entire `f system, It'heactuaiamountbeing-'determined similarly to the methodused in connection with thesystem of Figs. 1A to 10. `As air in small quan`1 `for admission. tosaid motor titywill be 'takeninto thefsystem upon each re-3 Vversalyofthe valve,'suitable= means for itsV discharge must be provided. Suchmeans must pre-3 Y ,floatvalve I I 8 .descriptionso-far given. r

.fluidatatmospheric.pressureacting upon one end overcome a magnetic.valve lioldingforce.A

Whue, there are in .this eppueatin speeinf clude, liquid discharge-'so'a combination-of aV and-,ajcheck valve l|9such as isvv show n iniFig. 12may be advantageouslyrusedn Av location at the. top of each 'diaphragmychamvber will be advisable;y ,and any suitable-,valve `means maybeemployed. The continuousvoperationof lthe'fpumpy will be apparentfromthe1 i6@ ofthe valve,v followinggthe production of a vac- Y' uum'latgthe other fendqof the valve; acting to In-bothembodimentsortheinventiomit: will i l be appreciatedfthat,therey isprovided acom- .1 paratively simpleconstruction of relativelylight 'l-weight,fcapableof theproduction of therequisite f pumping pressures,not likelyto beiinjulred bythe 1, presence. of. subst ances `inftl'iefliquid pumped i which would be harmflulfto ordinary steel,.reciplrocating-type pumps; and;v Vofl generalwapplicaj .tion, as well,asespeciallyadapted to the particf f 'ular eld for-whichthepresentvillustrative em l ,bodiments arepxjimarily intended. f

.ated vvalve having V4.Y In combination,l in

.ingon'eend of said valve l Y ceeding atmospheric, means forsubjectingfthe op# fled and vembodied -in various other forms withoutdeparting i'romvits spirit or the yscope of -the l appended claims.y

lWhat Ifclaim as new 1,. In combination, in a diaphragm p1in ip,` achamber having a movable diaphragm dividing its interior into pumpandmotor spaces, means for supplying and exhaustingmotive iiuid rela.

tive to said motor space actuated valve. and acontrolling passageincluding a pressure duid Space. i

V2.- InV combination, in .a .diaphragm"pump,l av

chamber havinga movable diaphragm dividing its `interior into pump "andmotor spacesmeans vfor supplying and exhausting motive iiuid relative tosaid.. motor space associated therewith means for holding the same hevalve is subjected to a greater pressure than is lifiorxriallv presentin said motor space during. displacement-.of fluid from said pump space,and ya throwing passage for said -valve connectedwith saidmotor 'spaceat apoint covered by said diaphragxn when said valve e space.V y 3,.. Incombination, in a diaphragm pump, a chamber having a diaphragm movablethereinfto vary inversely the of, inlet and .exhaust valvesffiy a iiuidto, be pumped connected with said chamber at one side of saiddiaphragm', means withdrawing Afromv the other sideof said diaphragm afluid underpressure, and means for switching the pressure .fluidconnections, said last mentioned means having .oppositely facingsurfaces one subjected to .atmosphericupressure to effectactuation ofsaid means when. the other surface. is subjected to subatmo'sphericpressure produced at one side of,saidl diaphragm rafter the latterreaches one ofits extreme positlons;

a pressure-nuid-operated pump having a'filuid actuated pump element,

lpump operating fluid Asupply mean'sincluding'a reversely movable valvefor controlling. thesuprplyoif pump operating iiuid; relative to saidpump element, magnetic means for holding said valvel in oppositeextremepositions, and means for subjecting the opposite end s of said .valvealter natelyto Lvacuum andto atmospheric pressurefto eiectthrowing ofsaidlvalve.

5.v In combination, in a pressuree-iluidfoperated pump yhaving a Viluidactuated Vpumpfelement,` pumpeoperating iluid supply means includingv aArevers'ely-movable valve for controlling rthe supply of pumpkope'ratingfluid relative' tofsaid pump elementmagnetic meansl for holding saidvalve in extreme opposite positions, meansfor subjectposite endr ofVvsaid valve tol a lower pressureto produce al dierential throwingypressure thereon, andV means actuated by 'said valve for ad-.inittingfpressur'e to restore thelower pressurelto atmospheric.

" v6.l,"n combination, in apr'essure-fluid-operated pumpliavingaAtluidfactuat-ed pump element..

-pump operating ifiuid supplymeans includinga Iit' will be understood ldesire to s ecure I for said .valve connected with said motor space at apointy covered by said diaphragm when'said valve as- .sumes'the-position for admission to saidmotor including a pressure iluidactuef against throwing except when assumesuthe .position f volumesatoppositesidestherf Iordelivering lto and toa pressure not exreverselymovable valve for controlling the supply of pump operating iluidrelative to said pump element, magnetic means for holding said valve inextreme opposite positions, means for subjecting one end oi said valveatmospheric, means forv subjecting the opposite end of said valve to alower pressure to produce a differential throwing pressure thereon, andmeans for admitting pressure to restore the lower pressure toatmospheric.

7. In combination, in a pressure-fluid-operated pump having a fluidactuated pump element, pump operating fluid supply means including areversely movable valve fr controlling the supply of pump operatingfluid relative to said pump element, permanent magnetic means forholding said valve in opposite extreme positions, and means foreffecting opposite throwing movements of said valve.

8. Infoombination, in a pressure-iluid-operated pumpv having a uidactuated pump element, pump operating fluid supply means including avalve for controlling the supply of pump operating fluid, springsfexerting opposite pressures on said valve in directions ter, pistonsmovable to vary the compression of said springs, and means forsubjecting said pisto a pressure not exceeding l tons alternately topressures transmitted"l past said valve.

9. In combination, ber pump, a distributing valve for supplyingpressures to effect discharge from one chamber and intake into the otherand viceversa in alternation, springs alternatively active to throw saidvalve, and means for loading said springs to a valve-throwing pressureincluding pistons coaxial longitudinally of the lat- 25 with said valve.

10. In a pump, chambers having` in combination, diaphragm diaphragmstherein dividing their interiors `into pump and motor spaces, meansk forsubjecting the motor space side of one diaphragm to pressure and themotor spaceside of the other to suction, means forreversing the'pressure conditions upon said diaphragms including a reclprocablymovable valve, means vfor connecting one end of said valve to atmospherewhen in oneof its extreme positions, and means subjected to thepressures in said motor spaces and operative at a predeterminedsubatmospheric pressure therein for connecting ythe other end of saidvalve to the motor space in which the subatmospheric pressure exists andproducing a` differential throwing pressure thereon.

ALEXANDER D. FERGUSON.

in a multi-Working-cham--

